Systems and methods associated with bottoming cycle power systems for generating power, capturing carbon dioxide and producing products

ABSTRACT

A bottoming cycle power system includes a turbo-expander operable to rotate a turbo-crankshaft as a flow of exhaust gas from a combustion process passes through the turbo-expander. A turbo-compressor is operable to compress the flow of exhaust gas after the exhaust gas passes through the turbo-expander. An open cycle absorption chiller system includes an absorber section operable to receive the flow of exhaust gas from the turbo-expander and to mix the flow of exhaust gas with a first refrigerant solution within the absorber section. The first refrigerant solution is operable to absorb water from the exhaust gas as the exhaust gas passes through the first refrigerant solution. The absorber section is operable to route the flow of exhaust gas to the turbo-compressor after the flow of exhaust gas has passed through the first refrigerant solution.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of, and claims priority to, U.S.patent application Ser. No. 17/448,938, filed on Sep. 27, 2021 andtitled: SYSTEMS AND METHODS ASSOCIATED WITH BOTTOMING CYCLE POWERSYSTEMS FOR GENERATING POWER, CAPTURING CARBON DIOXIDE AND PRODUCINGPRODUCTS; which is a continuation in part of, and which this applicationalso claims priority to, U.S. patent application Ser. No. 17/358,197,filed on Jun. 25, 2021 and titled: BOTTOMING CYCLE POWER SYSTEM. Thecontents of the prior applications are hereby incorporated by referenceherein in their entirety.

TECHNICAL FIELD

The present disclosure relates to systems and methods for generatingpower, capturing carbon dioxide and/or producing products from suchsystems and methods. More specifically, the disclosure relates tosystems and methods associated with bottoming cycle power systems forgenerating power, capturing carbon dioxide and/or producing products.

BACKGROUND

One of the most challenging aspects of today's energy technologies is toeffectively convert waste heat from a combustion process into useablepower, to effectively utilize such waste heat to produce products,and/or to capture the carbon dioxide from the exhaust gas of thatcombustion process. Such useable power can be in the form of electricalor mechanical power for use in stationary and/or mobile applications.

Methods of converting waste heat into useful forms of energy arecommonly referred to as bottoming cycles. Systems that utilize abottoming cycle to provide power are referred to herein as bottomingcycle power systems.

Systems that utilize a fuel combustion process in an internal combustionengine (such as a piston engine or a turbine engine) as the motive forceto drive a crankshaft for providing power are referred to herein asprimary power systems. In most primary power systems the efficiency ofthe system ranges from below 30% to a high of almost 50%. This meansthat the majority of energy contained in the fuel is lost in the form ofheat to the atmosphere through either the cooling circuit or exhaust ofthe internal combustion engine. Additionally, the less efficient aprimary power system is, the more carbon dioxide there is in the exhaustgas that gets emitted to the atmosphere.

However, the waste energy or exhaust gas from the internal combustionengine of a primary power system may be utilized as the energy input fora bottoming cycle power system. If enough useful work can be recoveredfrom such a bottoming cycle power system, the bottoming cycle powersystem could then be used to supplement the output of the primary powersystem for a more efficient overall combined power system output.

Some bottoming cycle power systems include a turbo-expander thatreceives a flow of exhaust gas from a combustion process, such as from acombustion process of an internal combustion engine. The exhaust gascarries a significant amount of energy. However, the flow of exhaust gasis typically only at, or slightly above, atmospheric pressure. Forexample, the exhaust pressure may be only a few pounds per square inch(psi) above atmospheric pressure. This makes recovering useful workdifficult. Additionally, the low pressures associated with the wasteheat makes utilizing such waste heat to produce useful products orcommodities, rather than just exhausting the waste heat to theatmosphere, more difficult.

In some bottoming cycle power systems, the exhaust gas flows through aturbo-expander where it typically exits the turbo-expander at belowatmospheric pressures (or vacuum pressures). The vacuum pressures arecaused by a compression turbine (or turbo-compressor). That is, theturbo-compressor is in fluid communication with the exit/output side ofthe turbo-expander and is operable to pull a vacuum on the output sideof the turbo-expander as the exhaust gas flows from the turbo-expanderto the turbo-compressor. Thereafter, the exhaust gas enters theturbo-compressor where it is pumped back to atmospheric pressure anddischarged to the atmosphere. The amount of energy recovered from such abottoming cycle power system is the energy produced by theturbo-expander minus the energy consumed by the turbo-compressor.Therefore, the less work needed by the turbo-compressor to compress theexpanded volume of exhaust gas, the higher the net-work produced fromthe bottoming cycle power system.

Various prior art cooling systems may be utilized to reduce the volume(or specific volume) of exhaust gas prior to entering theturbo-compressor of a bottoming cycle power system and therefore, reducethe amount of work required by the turbo-compressor to compress theexhaust gas. Problematically however, these cooling systems consume asignificant amount of energy due to pumps and/or other energy consumingdevices needed to circulate coolants through the cooling system.Additionally, such cooling systems often require a significant pressuredifferential for the exhaust gas to flow through, therefore reducing theamount of vacuum that the turbo-compressor can pull on theturbo-expander.

Moreover, the more the exhaust gas is cooled in order to produce as muchnet-work required of the turbo-compressor of a bottoming cycle powersystem as possible, the more the density of the cooled exhaust gas willincrease. Problematically, if the exhaust gas is cooled to ambient ornear ambient temperatures, the exhaust gas will become too dense to flowup the required stack (or chimney stack system) of the internalcombustion engine. In that case, the exhaust gas must be re-heated as itexits the turbo-compressor, which may significantly reduce the amount ofnet-work that the bottoming cycle power system can provide.

Further, the exhaust gas of an internal combustion engine contains asignificant amount of water vapor as a naturally occurring by-product ofthe combustion process. Problematically, the water vapor has arelatively high specific volume and mass, which causes an unwantedburden on the compression work of the turbo-compressor in the bottomingcycle power system.

Additionally, the exhaust gas of an internal combustion engine containsa significant amount of undesirable carbon dioxide, which is asignificant greenhouse gas. Problematically, prior art carbon dioxidecapture systems generally consume a significant amount of energy toremove the carbon dioxide from the exhaust gas, which would also cause aburden on the efficiency of the internal combustion engine. Alsoproblematically, the significant amount of water in the exhaust gas mayinterfere with the carbon dioxide capture process, making the carbondioxide capture process less efficient and more costly.

Accordingly, there is a need for a bottoming cycle power system whereinthe specific volume of flow of exhaust gas is significantly andefficiently reduced with as little pressure drop as possible afterexiting the turbo-expander and prior to entering the turbo-compressor.Also, there is a need to cool the exhaust gas to reduce the workrequired of the turbo-compressor in a bottoming cycle power system toincrease the overall efficiency of that bottoming cycle power system.Further there is a need to efficiently decrease the volume and mass ofwater vapor in a flow of exhaust gas prior to entering theturbo-compressor of a bottoming cycle power system. Moreover, there is aneed to capture carbon dioxide in a flow of exhaust gas from a bottomingcycle power system with as little energy consumption as possible.Additionally, there is a need to maintain the temperature of the exhaustgas from a bottoming cycle power system above a temperature that willenable the exhaust gas to readily flow up its associated stack.Moreover, there is a need to utilize the low pressure waste heat toefficiently produce products, which may beneficially further cool theexhaust gas prior to being exhausted to the atmosphere.

BRIEF DESCRIPTION

The present disclosure offers advantages and alternatives over the priorart by providing bottoming cycle power systems and methods for receivinga flow of exhaust gas from a combustion process into a turbo-expander,and for removing heat and water from the exhaust gas prior to enteringinto a turbo-compressor, to more efficiently generate power. The presentdisclosure also provides systems and methods for utilizing heat andwater removed from the exhaust gas of a combustion process toefficiently and cost effectively produce products, such as distilledwater, diesel exhaust fluid and recycled plastic products, rather thanjust exhausting the heat and water to the atmosphere. The presentdisclosure also provides systems and methods for capturing carbondioxide from the flow of exhaust gas.

The bottoming cycle power systems and methods may include aturbo-expander and a turbo-compressor. The turbo-expander expandsexhaust gas from a combustion process (such as a primary power system)as the exhaust gas passes through the turbo-expander. Theturbo-compressor pulls a vacuum on the exhaust gas on the exit side ofthe turbo-expander in order to increase the pressure differential acrossthe turbo-expander. The specific volume of flow of exhaust gas issignificantly and efficiently reduced with as little pressure drop aspossible after exiting the turbo-expander and prior to entering theturbo-compressor. The bottoming cycle power system may also include anopen cycle absorption chiller system, which is uniquely utilized to coolthe exhaust gas and to remove water from the exhaust gas. The removedwater may then be utilized to provide distilled water products, such asdistilled water or diesel exhaust fluid. A recycled plastic processingsystem may also be uniquely used to further cool the exhaust gas. Anexhaust gas heat exchanger may uniquely be used to further cool theexhaust gas prior to entering the turbo-compressor and to reheat theexhaust gas after it exits the turbo-compressor so that the exhaust gasreadily flows up a stack associated with the combustion process. Acarbon dioxide capture system may be used to remove carbon dioxide fromthe dry exhaust gas after the flow of exhaust gas has passed through theopen cycle absorption chiller system and the turbo-compressor.

A bottoming cycle power system in accordance with one or more aspects ofthe present disclosure includes a turbo-expander operable to rotate aturbo-crankshaft as a flow of exhaust gas from a combustion processpasses through the turbo-expander. A turbo-compressor is operable tocompress the flow of exhaust gas after the exhaust gas passes throughthe turbo-expander. An open cycle absorption chiller system includes anabsorber section operable to receive the flow of exhaust gas from theturbo-expander and to mix the flow of exhaust gas with a firstrefrigerant solution within the absorber section. The first refrigerantsolution is operable to absorb water from the exhaust gas as the exhaustgas passes through the first refrigerant solution. The absorber sectionis operable to route the flow of exhaust gas to the turbo-compressorafter the flow of exhaust gas has passed through the first refrigerantsolution.

It should be appreciated that all combinations of the foregoing conceptsand additional concepts discussed in greater detail below (provided suchconcepts are not mutually inconsistent) are contemplated as being partof the inventive subject matter disclosed herein and may be used toachieve the benefits and advantages described herein.

DRAWINGS

The disclosure will be more fully understood from the following detaileddescription taken in conjunction with the accompanying drawings, inwhich:

FIG. 1 depicts a schematic of an example of a combined power systemhaving a primary power system and a bottoming cycle power system,wherein the bottoming cycle power system includes a turbine generator, arecycle plastic processing system, an exhaust gas heat exchanger, anopen cycle absorption chiller system and a carbon dioxide capturesystem, in accordance with the present disclosure;

FIG. 2 depicts a schematic of an example of a detailed view of the opencycle absorption chiller system of FIG. 1 , in accordance with thepresent disclosure;

FIG. 3 depicts a schematic of an example of a detailed view of a coolingtower that may be used in the open cycle absorption chiller system ofFIG. 2 , in accordance with the present disclosure;

FIG. 4 depicts a schematic of an example of a detailed view of thecarbon dioxide capture system of FIG. 1 , in accordance with the presentdisclosure; and

FIG. 5 depicts a schematic of an extruder of the recycled plasticprocessing system of FIG. 1 , in accordance with the present disclosure.

FIG. 6 , depicts an example of a flow diagram of a method of generatingelectrical power, in accordance with the present disclosure;

FIG. 7A, depicts an example of a flow diagram of a method of capturingcarbon dioxide from a flow of exhaust gas, in accordance with thepresent disclosure;

FIG. 7B, depicts an example of a continuation of the flow diagram ofFIG. 9A of the method of capturing carbon dioxide from a flow of exhaustgas, in accordance with the present disclosure;

FIG. 8 , depicts an example of a flow diagram of a method of producingdistilled water products, in accordance with the present disclosure; and

FIG. 9 , depicts an example of a flow diagram of a method of producingrecycled plastic products, in accordance with the present disclosure.

DETAILED DESCRIPTION

Certain examples will now be described to provide an overallunderstanding of the principles of the structure, function, manufacture,and use of the methods, systems, and devices disclosed herein. One ormore examples are illustrated in the accompanying drawings. Thoseskilled in the art will understand that the methods, systems, anddevices specifically described herein and illustrated in theaccompanying drawings are non-limiting examples and that the scope ofthe present disclosure is defined solely by the claims. The featuresillustrated or described in connection with one example maybe combinedwith the features of other examples. Such modifications and variationsare intended to be included within the scope of the present disclosure.

The terms “significantly”, “substantially”, “approximately”, “about”,“relatively,” or other such similar terms that may be used throughoutthis disclosure, including the claims, are used to describe and accountfor small fluctuations, such as due to variations in processing from areference or parameter. Such small fluctuations include a zerofluctuation from the reference or parameter as well. For example, theycan refer to less than or equal to ±10%, such as less than or equal to±5%, such as less than or equal to ±2%, such as less than or equal to±1%, such as less than or equal to ±0.5%, such as less than or equal to±0.2%, such as less than or equal to ±0.1%, such as less than or equalto ±0.05%.

Referring to FIG. 1 , a schematic is depicted of an example of acombined power system 100 having a primary power system 102 and abottoming cycle power system 104, in accordance with the presentdisclosure. The bottoming cycle power system 104 includes a turbinegenerator 108, a recycle plastic processing system 110, an exhaust gasheat exchanger 112, an open cycle absorption chiller system 114 and acarbon dioxide capture system 106, in accordance with the presentdisclosure.

In this specific example, the combined power system 100, primary powersystem 102 and bottoming cycle power system 104 are configured togenerate electrical power to, for example, a grid (i.e., aninterconnected network for delivering electricity from producers toconsumers). However, it is within the scope of the present disclosure,that the power systems 100, 102 and 104 could be used to providemechanical power as well.

Moreover, such power systems of the present disclosure may be used inboth stationary applications and mobile applications. Examples of suchstationary applications include electric generator systems fordelivering electric power to a grid, electric generator systems fordelivering electric power to a building, mechanical power systems fordelivering mechanical power for an industrial manufacturing process orthe like. Examples of such mobile applications include mechanical powersystems for delivering mechanical power to a motor vehicle, electricalpower systems for delivering electrical power to an electric vehicle orthe like.

The primary power system 102 includes an internal combustion engine 116having an engine crankshaft 118 that is operatively connected to aprimary electric generator 120. The internal combustion engine 116 mayinclude a turbine engine, a piston engine or similar. The engine 116utilizes fuel in a combustion process as the motive force that rotatesthe engine crankshaft 118 and the primary electric generator 120 togenerate a first electrical output 122. Additionally, the combustionprocess produces a flow of exhaust gas 124, which may be routed to thebottoming cycle power system 104. The flow of exhaust gas 124 from thecombustion process of the internal combustion engine 116 may be at, ornear, atmospheric pressure and may have a temperature in the range of850 to 950 degrees Fahrenheit (F).

Though in this example, the combustion process and associated flow ofexhaust gas 124 is utilized within a primary power system 102, otherdevices and/or systems may utilize a combustion process to produceexhaust gas 124. For example, the exhaust gas 124 may be produced from afurnace system, or from burning natural gas at an oil well site or thelike.

The bottoming cycle power system 104 includes the turbine generator 108.The turbine generator 108 includes a turbo-expander 126 andturbo-compressor 128 disposed on a turbo-crankshaft 130. Theturbo-expander 126 is operable to rotate the turbo-crankshaft 130 as theflow of exhaust gas from a combustion process (such as, for example, thecombustion process generated from internal combustion engine 116) passesthrough the turbo-expander 126.

The turbo-expander 126 expands the exhaust gas 124 to extract energyfrom the exhaust gas 124 and convert the energy to work on thecrankshaft 130. Because the exhaust gas 124 is expanded as it passesthrough the turbo-expander 126, and because the turbo-compressor 128 isoperable to pull a vacuum on the exit or output side of theturbo-expander 126, the exhaust gas 124 may be under a vacuum as itexits the turbo-expander 126. For example, the exhaust gas 124 may be ata vacuum pressure of perhaps 0.2 atmospheres as it exits theturbo-expander 126. Additionally, the exhaust gas 124 will cool as itperforms work on the crankshaft 130, for example within a range of500-700 degrees F.

The turbo-compressor 128 (typically a turbine compressor or similar) isoperatively connected to the flow of exhaust gas 124. More specifically,as the turbo-compressor 128 is rotated by the turbo-crankshaft 130, theturbo-compressor 128 is operable to compress the flow of exhaust gas 124after the exhaust gas passes through the turbo-expander 126, therecycled plastic processing system 110, the exhaust gas heat exchanger112 and the open cycle absorption system 114.

Moreover, the turbo-compressor 128 pulls a vacuum on the output side ofthe turbo-expander 126 (for example a vacuum of about 0.2 atmospheres)to increase a pressure difference across the turbo-expander 126. Theincreased pressure difference enhances the expansion of the flow ofexhaust gas 124 through the turbo-expander 126 in order to enhance theconversion of energy in the exhaust gas 124 into usable work on theturbo-crankshaft 130.

A bottoming cycle generator 132 is also disposed on the turbo-crankshaft130. The bottoming cycle generator 132 is operable to generateelectrical power when the turbo-crankshaft 130 is rotated by theturbo-expander 126. In other words, the bottoming cycle generator 132generates a second electrical output 134 that may be used to supplementthe first electrical output 122 of the primary power system 102.

The exhaust gas 124 may flow from the turbo-expander 126 into therecycled plastic processing system 110. The recycled plastic processingsystem 110 is operable to receive the flow of exhaust gas 124 from theturbo-expander 126 and to route the flow of exhaust gas 124 to the opencycle absorption system 114. The recycled plastic processing system 110is operable to remove heat from the flow of exhaust gas 124 with verylittle pressure drop.

Advantageously, the recycled plastic processing system 110 cools theexhaust gas 124 and increases the density of the exhaust gas 124, whichreduces the amount of work required of the turbo-compressor 128 to pumpthe exhaust gas 124 back to atmospheric pressures. Additionally, becausethe flow of exhaust gas 124 encounters very little pressure drop throughthe recycled plastic processing system 110, the vacuum pressure at theoutput side of the turbo-expander 126, as well as the pressuredifferential across the turbo-expander 126, is largely maintained.Therefore, the enhanced work output of the turbo-expander 126 is alsomaintained.

With the enhanced work output of the turbo-expander 126 and the reducedamount of work required from the turbo-compressor 128, the secondelectrical output 134 may be large enough to provide a portion of, orall of, the electrical power to operate the recycled plastic processingsystem 110, the open cycle absorption chiller system 114 and/or thecarbon dioxide capture system 106. For example, the bottoming cyclegenerator 132 may be operable to generate electrical power to operateall of, or a portion of, the recycled plastic processing system 110 whenthe turbo-crankshaft 130 is rotated by the turbo-expander 126. Also, thebottoming cycle generator 132 may be operable to generate electricalpower to operate all of, or a portion of, the open cycle absorptionchiller system 114 when the turbo-crankshaft 130 is rotated by theturbo-expander 126. Also, the bottoming cycle generator 132 may beoperable to generate electrical power to operate all of, or a portionof, the carbon dioxide capture system 106 when the turbo-crankshaft 130is rotated by the turbo-expander 126. Also, the bottoming cyclegenerator 132 may be operable to generate electrical power to operateall of, or a portion of, any combination of the recycled plasticprocessing system, the open cycle absorption chiller system 114 and thecarbon dioxide capture system when the turbo-crankshaft 130 is rotatedby the turbo-expander 126.

Also advantageously and as will be explained in greater detail herein,the heat removed from the flow of exhaust gas 124 may be used by therecycled plastic processing system 110 to melt solid recyclable plasticmaterials 308 to provide a flow of molten recyclable plastic material310 (see FIG. 5 ). The molten recyclable plastic material 310 isoperable to be cooled into a solid recycled plastic product 312 (seeFIG. 5 ), such as bottles 312A, furniture 312B, clothing 312C or thelike. By utilizing waste heat energy from the flow of exhaust gas 124,rather than generating heat energy from other more traditional primarysources of energy (such as electricity, natural gas, coal or the like),to melt such recyclable plastic materials 308, the cost of providingrecycled plastic products 312 is greatly reduced. Moreover, the cost ofproviding such recycled plastic products 312 utilizing energy from theexhaust gas 124 in the recycled plastic processing system 110 may bereduced below the cost of producing those equivalent products as new,non-recycled products. Therefore, the incentive to recycle plastic,instead of dispose of plastic in, for example, landfills, may be greatlyenhanced in general.

The recycled plastic processing system 110 may be advantageouslydisposed within the bottoming cycle power system 104 such that itreceives the flow of exhaust gas 124 directly from the turbo-expander126 and prior to the exhaust gas entering either the exhaust gas heatexchanger 112 or the open cycle absorption chiller system 114. This isbecause, the exhaust gas heat exchanger 112 and the open cycleabsorption chiller system 114 both cool the exhaust gas 124 further,which, in some cases, may drop the temperature of the exhaust gas 124below the melting point of some recyclable plastic materials 308.Additionally, by disposing the recycled plastic processing system 110 inthe flow of exhaust gas upstream of the exhaust gas heat exchanger 112and the open cycle absorption chiller system 114, both the exhaust gasheat exchanger 112 and the open cycle absorption chiller system 114 maybe downsized significantly.

From the recycled plastic processing system 110, the exhaust gas 124 mayflow into the exhaust gas heat exchanger 112. The exhaust gas heatexchanger 112 includes a first flow path 136 and a second flow path 138operable to exchange heat therebetween. More specifically, the firstflow path 136 is operable to transfer heat into the second flow path138. The first flow path 136 is operable to receive the flow of exhaustgas 124 from the turbo-expander 126 prior to the exhaust gas 124 beingcompressed by the turbo-compressor 128. More specifically in thisexample illustrated in FIG. 1 , the first flow path 136 is operable toreceive the flow of exhaust gas 124 from the turbo-expander 126 afterthe exhaust gas has passed through the recycled plastic processingsystem 110. The second flow path 138 is operable to receive the flow ofexhaust gas 124 from the turbo-compressor 128 after the exhaust gas 124has been compressed by the turbo-compressor 128. More specifically inthis example illustrated in FIG. 1 , the second flow path 138 isoperable to receive the flow of exhaust gas 124 from theturbo-compressor 128 after it has passed through the carbon dioxidecapture system 106.

The hot exhaust gas 124 from the turbo-expander 126 (for example atabout a temperature of 500-700 degrees F.) or from the recycled plasticprocessing system (for example at about 300-400 degrees F.), that flowsthrough the first flow path 136 of the exhaust gas heat exchanger 112,is cooled by the much cooler exhaust gas 124 (for example at about atemperature range of 60-80 degrees F.) from the turbo-compressor 128,that flows through the second flow path 138 of the exhaust gas heatexchanger 112. Advantageously, the cooled exhaust gas 124 from theturbo-compressor 128 provides a stage of cooling for the hotter exhaustgas 124 from the turbo-expander 126. For example, the exhaust gas 124may be cooled down to about a range of 200-300 degrees F. as it exitsthe first path 134 of the exhaust gas heat exchanger 112.

Also, advantageously, the hotter exhaust gas 124 from the turbo-expander126 or recycled plastic processing system 110 reheats the cooler exhaustgas 124 from the turbo-compressor 128 to temperatures that enable theexhaust gas 124 to flow readily up a stack 140 of the combined powersystem 100. For example, the exhaust gas 124 exiting the second path 136of the gas heat exchanger 112 may be within a range of about 150-250degrees F.

The stack 140, as used herein, will refer to the extended exhaust pipingsystem (or chimney stack system) designed to route exhaust gas away fromthe source of the combustion process (in this example, the source of thecombustion process is the internal combustion engine 116). In thisexample, the stack 140 of the combined power system 100 is designed toroute the flow of exhaust gas 124 away from the combined power system100 after the exhaust gas exits the second flow path 138 of the exhaustgas heat exchanger 112).

The stack 140 of the combined power system 100 is utilized to route theexhaust gas 124 away from the combined power system 100 and to maintainair quality in the proximity of the combined power system 100. The stack140, often by regulation, may have a minimum height that may be as muchas 1.5 times the height of a building or container that houses theengine 116 or more. If the exhaust gas 124 is too cool (for example,near or below ambient temperature), the exhaust gas 124 will be toodense to readily flow to the top of the stack 140. Cooling the exhaustgas 124 to near ambient temperature before it enters theturbo-compressor 128 is advantageous for increasing the compressionratio (and therefore efficiency) across the turbo-expander 126. However,reheating the exhaust gas 124 to temperatures that are significantlyhigher than ambient temperature after the exhaust gas 124 exits theturbo-compressor 128 is advantageous for routing the exhaust gas 124 upthe stack 140. The exhaust gas heat exchanger 112 helps to perform bothof these functions.

The open cycle absorption chiller system 114 is operable to receive,cool and remove water from the flow of exhaust gas 124 after the exhaustgas 124 has passed through the first flow path 136 of the exhaust gasheat exchanger 112 and prior to the exhaust gas 124 being compressed bythe turbo-compressor 128. The open cycle absorption chiller system 114provides another stage of cooling for the exhaust gas 124, andadditionally removes a significant amount of water from the exhaust gas124, prior to the exhaust gas 124 entering the turbo-compressor 128.0052. The carbon dioxide capture system 106 is operable to remove andcapture carbon dioxide 206 from the exhaust gas 124 after the exhaustgas 124 exits the turbo-compressor 128 and prior to the exhaust gas 124flowing through the second flow path 138 of the exhaust gas heatexchanger 112. As will be explained in greater detail herein, the carbondioxide capture system 106 is also operable to advantageously regeneratethe captured carbon dioxide 206 using a heat of compression of a carbondioxide compressor 220 (see FIG. 4 ).

Referring to FIG. 2 , a schematic is depicted of an example of adetailed view of the open cycle absorption chiller system 114, inaccordance with the present disclosure. The open cycle absorptionchiller system 114 has an absorber section 150, a generator section 152and a condenser section 154 all in fluid communication with each otherand operable to route a flow of water as a refrigerant therethrough. Inthe open cycle absorption chiller system 114, the exhaust gas 124 firstflows into a generator section heat exchanger 156 of the generatorsection 152 where the exhaust gas 124 is cooled. The exhaust gas 124then exits the generator section 152 and flows into the absorber section150 where the exhaust gas 124 is dried, i.e., water is removed from theexhaust gas 124.

The absorber section 150 is operable to receive the flow of exhaust gas124 from the turbo-expander 126. More specifically, the absorber section150 is operable to receive the flow of exhaust gas 124 from thegenerator section heat exchanger 156 after it has been cooled by thegenerator section 152. The absorber section 150 includes a firstrefrigerant solution 158 of water and a hygroscopic substance such as,for example, salt. The salt may be lithium bromide, lithium chloride orthe like. The first refrigerant solution 158 is operable to absorb waterfrom the exhaust gas 124 as the exhaust gas passes through the firstrefrigerant solution 158. The absorber section 150 is also operable toroute the flow of exhaust gas 124 to the turbo-compressor 128 after theflow of exhaust gas 124 has passed through the first refrigerantsolution 158.

The hygroscopic material in the first refrigerant solution 158 acts as astrong desiccant which removes a significant portion of water from theexhaust gas 124. The water from the exhaust gas, in turn, increases theconcentration of water in the first refrigerant solution 158, whereinthe water functions as a refrigerant in the first refrigerant solution158. More specifically, due to the high concentration of hygroscopicmaterial in the first refrigerant solution 158, the absorber section 150is advantageously operable to reduce the concentration of water in theflow of exhaust gas 124 to no more than 5.0 percent by weight, to nomore than 2.5 percent by weigh and/or to no more than 0.5 percent byweight before the flow of exhaust gas 124 exits the absorber section 150and/or before the flow of exhaust gas 124 enters the turbo-compressor128.

By advantageously reducing the content of water in the exhaust gas 124to these concentrations, both the mass and volume of the flow of exhaustgas 124 is significantly reduced, which further reduces work required ofthe turbo-compressor 128 and increases the overall efficiency of thebottoming cycle power system 104. Further, by advantageously reducingthe content of water in the exhaust gas 124 to these concentrations, theefficiency of the carbon dioxide capture system 106 is significantlyincreased. This is because water interferes with the absorption ofcarbon dioxide 206 in the carbon dioxide capture system 106.

The generator section 152 is operable to contain a second refrigerantsolution 160, which is in fluid communication with the first refrigerantsolution 158 of the absorber section 150. The second refrigerantsolution 160, like the first refrigerant solution 158, includes aconcentration of water and the hygroscopic substance, such as, forexample, salt. The salt may be lithium bromide, lithium chloride or thelike. More specifically, a refrigerant solution pump 162 is used to pumpthe first refrigerant solution 158, including water absorbed from theexhaust gas 124 into the first refrigerant solution 158, from theabsorber section 150 to the generator section 160 through refrigerantline 164. The first refrigerant solution 158, including the waterabsorbed from the exhaust gas 124, then mixes into the secondrefrigerant solution 160 in the generator section 152. The secondrefrigerant solution 160 flows (for example via being gravity fed) fromthe generator section 160 to the absorber section 150 throughrefrigerant line 166.

The absorber section 150, generator section 152 and condenser section154 may operate at vacuum pressures (i.e., below atmospheric pressures),when the exhaust gas 124 is routed from the turbo-expander 126 androuted to the turbo-compressor 128. However, the absorber section 150may operate at a lower vacuum pressure than the generator section 152and condenser section 154. For example, the absorber section 150 may beoperating at a vacuum pressure of approximately 0.1 atmospheres whilethe generator section 152 and condenser section 154 may be operating ata vacuum pressure of approximately 0.5 atmospheres. During operation,the water 161 in the flow of second refrigerant through line 166 getsabsorbed by the hygroscopic material (e.g., salt) as it enters theabsorber section 150 from the generator section 152 and gives off heatas it is absorbed. Accordingly, an absorber section heat exchanger 170disposed in the absorber section 150 may be in fluid communication to,for example, a water tower 172 via a cooling tower coolant loop 186. Theabsorber section heat exchanger 170 is used to cool the water 161 of thesecond refrigerant solution 160 as it mixes with the first refrigerantsolution 158 in the absorber section 150.

Though the open cycle absorption chiller system 114 has been describedas operating in a vacuum, it is within the scope of this disclosure thatthe open cycle absorption chiller system 114 may not operate in avacuum. For example, the open cycle absorption chiller system 114 maynot be connected to a turbine generator 108, wherein the open cycleabsorption chiller system 114 may be operating at pressures above oneatmosphere.

The generator section 152 includes the generator section heat exchanger156, which is operable to receive the flow of exhaust gas 124 from theturbo-expander 126. More specifically, in this example, the generatorsection heat exchanger 156 receives the exhaust gas 124 after it hasflowed through the turbo-expander 126, the recycled plastic processingsystem 110 and the exhaust gas heat exchanger 112.

The generator section heat exchanger 156 is operable to remove heat fromthe flow of exhaust gas 124 and to transfer the heat to the secondrefrigerant solution 160 in order to evaporate water from the secondrefrigerant solution 160 and to generate a flow of steam 168 as theexhaust gas 124 passes through the generator section heat exchanger 156.Evaporating water from the second refrigerant solution 160 to generatethe flow of steam 168, in turn, reduces the concentration of water inthe second refrigerant solution. The flow of steam 168 includes aportion, if not substantially all, of the same water absorbed from theflow of exhaust gas 124 by the first refrigerant solution 158 in theabsorber section 150. Steam 168, as used herein, may be composed ofsubstantially all water in its gas phase (e.g., water vapor) or may becomposed of water in its gas phase and plus water droplets in liquidphase.

Uniquely, the heat absorbed from the exhaust gas 124 in the generatorsection 152 is used to evaporate out of the second refrigerant solution160 the water absorbed from the exhaust gas 124 into the firstrefrigerant solution 158 in the absorber section 150. Advantageouslywithin this open cycle absorption chiller system 114, most of the energyrequired to remove, evaporate and distill water from the exhaust gas 124is provided by the heat energy of the exhaust gas 124 itself. Also,advantageously within this system 114, a substantial amount ofevaporative cooling of the exhaust gas 124 is provided by the waterabsorbed from the exhaust gas 124 itself. Accordingly, the exhaust gas124 is both dried and cooled with very little energy consumed fromsources outside of the energy contained within the exhaust gas 124. As aresult, the exhaust gas 124, having been dried and cooled by theuniquely configured open cycle absorption chiller system 114, can moreeasily be compressed by turbo-compressor 128 and can more efficientlyhave its carbon dioxide removed by carbon dioxide capture system 106.

The condenser section 154 is operable to be in fluid communication withthe flow of steam 168 from the generator section 152. The condensersection 154 includes a condenser section heat exchanger 174, which mayalso be in fluid communication with water tower 172 via the coolingtower coolant loop 186. Accordingly, the condenser section heatexchanger 174 of the condenser section 154 is operable to remove heatfrom the flow of steam 168 and to condense the flow of steam into a flowof liquid distilled water 176. The flow of liquid water includes aportion, if not all, of the same water absorbed by the first refrigerantsolution 158 from the flow of exhaust gas 124 in the absorber section150.

A water pump 180 is in fluid communication with the condenser section154. The water pump 180 is operable to pump the flow of liquid distilledwater 176 into a water tank 182. Advantageously, this distilled water176 includes the water removed from the exhaust gas 124 as it passedthrough the absorber section 150. The distilled water 176 is distilleddue to its evaporation in the generator section 152 and may be easilyand inexpensively processed into a distilled water products that meetscommercial standards. Also advantageously, the open cycle absorptionchiller system 114 operates such that the flow of water removed from theexhaust gas 124 in the absorber section 150 is balanced by the flow ofdistilled water 176 condensed in the condenser section 154 and collectedas liquid distilled water 176 in the water tank 182.

At this point, the distilled water 176 may be further processed intoother distilled water products. Examples of distilled water productsthat may be produced from the distilled water 176 would be:

-   -   distilled water for medical uses, use in fish aquariums and/or        watering plants such as plants grown for the legal Cannabis        industry;    -   deionized water for hygiene products such as shampoo,        conditioners or moisturizers; and    -   diesel exhaust fluid (DEF) (ref no. 183 in FIG. 2 ) for the        automotive industry.

Diesel exhaust fluid (DEF) 183, as referred to herein, is a liquid whichmay be used to reduce the amount of air pollution created by a dieselengine. Specifically, DEF is an aqueous urea solution made with about(within plus or minus five percent) one third urea and two thirdsdistilled or deionized water. More specifically DEF may be a solution of(within plus or minus one percent) 32.5 percent urea by mass and 67.5percent deionized water or distilled water by mass. Even morespecifically, DEF may also be defined by international standard ISO22241 of the International Organization for Standardization having aheadquarters in Geneva, Switzerland, which is incorporated herein byreference in its entirety. DEF may be consumed in selective catalyticreduction within a diesel engine that lowers the concentration ofnitrogen oxides (NOx) in the diesel exhaust emissions from the dieselengine.

As illustrated in FIG. 2 , in order to produce DEF 183, the organicchemical compound urea 181 must be added to the distilled water 176.Urea 181 may also be known as carbamide, and may have the chemicalformula CO(NH₂)₂. Urea 181 serves an important role in the metabolism ofnitrogen-containing compounds by animals and is the mainnitrogen-containing substance in the urine of mammals.

Though the exemplary embodiments illustrated in the FIGS. depicts theexhaust gas 124 being routed through an open loop absorption chillersystem 114 of a combined power system 100, it is within the scope ofthis disclosure that such an open loop absorption chiller system 114 maybe used in other embodiments as well. For example, the exhaust gas 124may be generated from a combustion process of a primary power system 102and routed directly to the open loop absorption chiller system 114without going through a bottoming cycle power system 104. Additionally,the combustion process may be generated from a source other than aprimary power system 102, such as from a furnace system or from burningnatural gas at an oil well site. In any of these cases, the open loopabsorption chiller system 114 may be utilized to remove water from theexhaust gas 124 and/or cool the exhaust gas 124. Moreover, utilizing anopen loop absorption chiller system 114 to remove water from exhaust gas124 generated by a combustion process of, for example, a primary powersystem 102, may significantly enhance the efficiency of a carbon dioxidecapture system 106, regardless of whether or not a bottoming cycle powersystem 104 is utilized.

Referring to FIG. 3 , a schematic is depicted of an example of adetailed view of the cooling tower 172 that may be used in the opencycle absorption chiller system 114, in accordance with the presentdisclosure. In this specific example, the cooling tower coolant fluid184 that flows through the cooling tower coolant loop 186 is water.However, other cooling tower coolant fluids may also be used or includedwith the water, such as, for example, glycol or the like.

During operation, a cooling tower coolant pump 188 may be used tocirculate the water (cooling tower coolant fluid) 184 through thecooling tower coolant loop 186 between the absorber section heatexchanger 170 of the absorber section 154 (see FIG. 2 ), the condensersection heat exchanger 174 of the condenser section 154 (see FIG. 2 )and the water tower 172. The water 184 from the water tower 172 mayenter the absorber section heat exchanger 170 in a range of about 70 to90 degrees F. The water from the condenser section heat exchanger 174may enter the upper portion 190 of the water tower 172 in a range ofabout 140 to 180 degrees F. 0071. After passing through the absorbersection 150 and condenser section 154, the heated water 184 will returnto the upper portion 190 of the water tower 172 where the water entersthe water tower's coolant distribution system 191. The coolantdistribution system 191 will route the water 184 through a plurality ofcooling tower nozzles 192, which will spray the water 184 onto a fillmaterial 193. The fill material (or fill media) 193 is a material usedto increase the surface area of the cooling tower 172. The fill material193 may be, for example, knitted metal wire, ceramic rings or othermaterials that provide a large surface area when positioned or packedtogether within the cooling tower 172. The fill material 193 slows thewater 184 down and exposes a large amount of water surface area toair-water contact.

Ambient air 194 is pulled through a lower portion 195 of the coolingtower 172 and out the upper portion 190 of the cooling tower 172 via acooling tower fan 196. A small amount of water 184 evaporates as the air194 and water 184 contact each other in the fill material 193, whichcools the water. For example, the water 184 may be cooled down to arange of about 70 to 90 degrees F.

The cooled water 184 falls into a collection basin 198, which adds backmake-up water to compensate for the small amount of water that has beenevaporated during the evaporative cooling process. The cooled water 184is then pumped through the cooling tower coolant loop 186 back to theabsorber section heat exchanger 170 via the cooling tower coolant pump188 to complete the refrigeration cycle.

The cooling tower 172 may be one of several types of cooling towers,such as crossflow cooling towers, counterflow cooling towers, open loopcooling towers, closed loop cooling towers or the like. However, theymost often operate utilizing evaporative cooling produced from air tocooling tower coolant fluid (e.g., water) contact.

Referring to FIG. 4 , a schematic is depicted of an example of adetailed view of the carbon dioxide capture system 106 utilized in thecombined power system 100, in accordance with the present disclosure. Asthe exhaust gas 124 exits the turbo-compressor 128 it will undesirablycontain carbon dioxide 206. To remove the carbon dioxide 206 prior toentering the exhaust gas heat exchanger 112, the carbon dioxide capturesystem 106 may be utilized.

The carbon dioxide capture system 106 includes a first capture tank 200and a second capture tank 202. Each capture tank 200, 202 containscarbon dioxide absorbent material 204 operable to absorb carbon dioxide206 from the exhaust gas 116. The carbon dioxide absorbent material maybe zeolite, metal organic frameworks material, calcium hydroxide or thelike.

It is important to note that because the exhaust gas 124 has passedthrough the hygroscopic material in the first refrigerant solution 158of the absorber section 150 of the open cycle absorption chiller system114 (see FIG. 2 ) prior to entering the carbon dioxide capture system106, the concentration of water in the exhaust gas has been greatlyreduced. For example, the concentration of water in the flow of exhaustgas 124 may be reduced to no more than 5.0 percent by weight, to no morethan 2.5 percent by weight and/or to no more than 0.5 percent by weightbefore the flow of exhaust gas 124 enters the carbon dioxide capturesystem 106. Since water interferes with the absorption of carbon dioxide206 by the carbon dioxide absorbent material 204, the efficiency of thecarbon dioxide capture system 106 is advantageously enhanced by suchreduction of the concentration of water in the exhaust gas 124.

Though the exemplary embodiments illustrated in the FIGS. depicts theexhaust gas 124 being routed through an open loop absorption chillersystem 114 of a combined power system 100 prior to entering the carbondioxide capture system 106, it is within the scope of this disclosurethat such an open loop absorption chiller system 114 and carbon dioxidecapture system 106 may be used in other embodiments as well. Forexample, the exhaust gas 124 may be generated from a combustion processof a primary power system 102 and routed directly to the open loopabsorption chiller system 114, which may then be routed directly to thecarbon dioxide capture system 106 without going through a bottomingcycle power system 104. Additionally, the combustion process may begenerated from a source other than a primary power system 102, such asfrom a furnace system or from burning natural gas at an oil well site.Moreover, utilizing an open loop absorption chiller system 114 to removewater from exhaust gas 124 generated by a combustion process of, forexample, a primary power system 102, may significantly enhance theefficiency of a carbon dioxide capture system 106, regardless of whetheror not a bottoming cycle power system 104 is utilized.

The first and second capture tanks 200, 202 each include an exhaust gasinlet port 208A and 208B, which are selectively connectable to the flowof exhaust gas 124 from the turbo-compressor 128. In other words, theexhaust gas inlet ports 208A and 208B are selectively connectable to theflow of exhaust gas 124 prior to the exhaust gas passing through thecarbon dioxide absorbent material 204. More specifically, flow valve210A controls flow of exhaust gas 124 into the exhaust gas inlet port208A of the first capture tank 200 and flow valve 210B controls flow ofexhaust gas 124 into the exhaust gas inlet port 208B of the secondcapture tank 202.

The first and second capture tanks 200, 202 also include an exhaust gasoutlet port 212A and 212B, which are selectively connectable to thesecond flow path 138 of the exhaust gas heat exchanger 112. In otherwords, the exhaust gas outlet ports 212A and 212B are selectivelyconnectable to the flow of exhaust gas after the flow of exhaust gas haspassed through carbon dioxide absorbent material. More specifically,flow valve 214A controls flow of exhaust gas 124 out of the exhaust gasoutlet port 212A of the first capture tank 200 and into the second flowpath 138 of the exhaust gas heat exchanger 112. Additionally, flow valve214B controls flow of exhaust gas 124 out of the exhaust gas outlet port212B of the second capture tank 202 and into the second flow path 138 ofthe exhaust gas heat exchanger 112.

The first and second capture tanks 200, 202 also include a carbondioxide outlet port 216A and 216B, which are selectively connectable toa carbon dioxide compressor 220. More specifically, flow valve 218Acontrols flow of regenerated carbon dioxide 206 out of the carbondioxide outlet port 216A of the first capture tank 200 and into thecarbon dioxide compressor 220. Additionally, flow valve 218B controlsflow of regenerated carbon dioxide 206 out of the carbon dioxide outletport 216B of the second capture tank 202 and into the carbon dioxidecompressor 220. The carbon dioxide compressor 220 is operable to pumpcarbon dioxide 206 out of the carbon dioxide outlet ports 216A, 216Bthat the carbon dioxide compressor 220 is connected to. The carbondioxide compressor 220 may be a rotary screw type compressor, a pistoncompressor or the like.

A compressor coolant loop 222 is selectively connectable between thecarbon dioxide compressor 220 and the first capture tank 200 or betweenthe carbon dioxide compressor 220 and the second capture tank 202. Thecompressor coolant loop 222 is operable to flow a compressor coolantfluid 224 (such as water, glycol of the like) to remove a heat ofcompression from the compressor 220 and to transfer the heat ofcompression to the first or second capture tanks 200, 202. The heat ofcompression is operable to release a portion of the carbon dioxide 206absorbed by the carbon dioxide absorbent material 204 in the first orsecond capture tanks 200, 202.

More specifically, the compressor coolant loop 222 includes a compressorcoolant jacket 226 of the compressor 220, a first capture tank heatingjacket 228 of the first capture tank 200 and a second capture tankheating jacket 230 of the second capture tank 202. The compressorcoolant jacket 226 is operable to contain and circulate the compressorcoolant fluid 224 around the outer surface of the compressor 220 to coolthe compressor 220. The compressor coolant fluid 224 will remove theheat of compression from the compressor 220.

For purposes herein, a heating or coolant jacket (such as coolant jacket226, and heating jackets 228 and 230) may refer to an outer casing orsystem of tubing, which holds fluid and through which the fluidcirculates to cool or heat a vessel or device. For example, thecompressor coolant jacket 226 may be a casing which surrounds the carbondioxide compressor 220 to enable the coolant fluid to absorb the heat ofcompression and to cool the compressor 220. Also, the first and secondcapture tank heating jackets 228 and 230 may be casings or systems oftubing, which are operable to transfer the heat of compression to theselected first or second capture tanks 200, 202 and to heat the carbondioxide 206 captured within the selected tank 200, 202.

The heating jackets 228 and 230 are operable to selectively contain andcirculate the compressor coolant fluid 224 (which is heated with theheat of compression from compressor 220) around the outer surfaces ofthe first or second capture tanks 200, 202 respectively to heat theselected capture tank 200, 202. The compressor coolant fluid 224 willadd the heat of compression to the selected capture tank 200, 202. Theheat of compression from the compressor 220 will then advantageously beused to regenerate (or desorb) a portion, or substantially all, of thecarbon dioxide 206 from the carbon dioxide absorbent material 204 sothat it can be pumped by the compressor 220 into a holding tank 232 forlater use and/or disposal.

A carbon dioxide heat exchanger 244 may be disposed between the holdingtank 232 and the carbon dioxide compressor 220 to cool the carbondioxide 206 prior to entering the holding tank 232. The carbon dioxideheat exchanger 244 may be cooled by a cooling tower 246 that circulatescoolant fluid between the cooling tower 246 and the carbon dioxide heatexchanger 244 via carbon dioxide heat exchanger coolant loop 248.

The compressor coolant fluid 224 is pumped around the compressor coolantloop 222 via pump 234. Flow valves 236, 238, 240 and 242 control theflow of compressor coolant fluid 224 to either the first capture tank200 or second capture tank 202. More specifically, when valves 236 and238 are open, and valves 240 and 242 are closed, the coolant loop 222circulates the coolant fluid 224 via pump 234 between the compressor 220and the first capture tank 200. In this configuration, the compressor220 is cooled and the first capture tank 200 is heated. When the valves236 and 238 are closed, and valves 240 and 242 are open, the coolantloop 222 circulates the coolant fluid 224 via pump 234 between thecompressor 220 and the second capture tank 202. In this configuration,the compressor 220 is cooled and the second capture tank 202 is heated.

During operation, the various flow valves may be configured such thatthe exhaust gas inlet port 208A of the first capture tank 200 isconnected (i.e., in fluid communication) to the flow of exhaust gas 124from the turbo-compressor 128. In other words, the exhaust gas inletport 208A is connected to the flow of exhaust gas 124 prior to theexhaust gas 124 passing through the carbon dioxide absorbent material204. Additionally, the first capture tank's exhaust gas outlet port 212Ais connected (i.e., in fluid communication) to the second flow path 138of the exhaust gas heat exchanger 112. In other words, the exhaust gasoutlet port 212A is connected to the flow of exhaust gas 124 after theexhaust gas has passed through the carbon dioxide absorbent material204. Additionally, the carbon dioxide compressor 220 may be connected tothe carbon dioxide outlet port 216B of the second capture tank 202 andthe compressor coolant loop 222 may be connected between the carbondioxide compressor 220 and the second capture tank 202. In thisconfiguration, exhaust gas 124 will flow into the first capture tank 200to remove the carbon dioxide 206 from the exhaust gas 124 flow prior toentering the exhaust gas heat exchanger 112. Simultaneously, the heat ofcompression from the carbon dioxide compressor 220 will advantageouslybe used to heat the second capture tank 202 to regenerate the carbondioxide from the second capture tank 202 and to pump the carbon dioxide206 into the holding tank 232. By using the heat of compression of thecarbon dioxide compressor 220 to regenerate the carbon dioxide in thesecond capture tank 202, the energy needed from external sources (suchas electric heaters or the like) to regenerate the carbon dioxide isadvantageously reduced.

Also during operation, the various flow valves may be configured suchthat the exhaust gas inlet port 208B of the second capture tank 202 isconnected (i.e., in fluid communication) to the flow of exhaust gas 124from the turbo-compressor 124. In other words, the exhaust gas inletport 208B is connected to the flow of exhaust gas 124 prior to theexhaust gas 124 passing through the carbon dioxide absorbent material204. Additionally, the second capture tank's exhaust gas outlet port212B is connected (i.e., in fluid communication) to the second flow path138 of the exhaust gas heat exchanger 112. In other words, exhaust gasoutlet port 212B is connected to the flow of exhaust gas 124 after theexhaust gas 124 has passed through the carbon dioxide absorbent material204. Additionally, the carbon dioxide compressor 220 may be connected tothe carbon dioxide outlet port 216A of the first capture tank 200 andthe compressor coolant loop 222 may be connected between the carbondioxide compressor 220 and the first capture tank 200. In thisconfiguration, exhaust gas will flow into the second capture tank 202 toremove the carbon dioxide 206 from the exhaust gas 124 flow prior toentering the exhaust gas heat exchanger 112. Simultaneously, the heat ofcompression from the carbon dioxide compressor 220 will advantageouslybe used to heat the first capture tank 200 to regenerate the carbondioxide from the first capture tank 200 and pump the carbon dioxide intothe holding tank 232. By using the heat of compression of the carbondioxide compressor 220 to regenerate the carbon dioxide in the firstcapture tank 200, the energy needed from external sources (such aselectric heaters or the like) to regenerate the carbon dioxide isadvantageously reduced.

Referring to FIG. 5 , a schematic is depicted of an extruder 300 of therecycled plastic processing system 110 of FIG. 1 , in accordance withthe present disclosure. The recycled plastic processing system 110 isoperable to receive the flow of exhaust gas 124 from the turbo-expander124 and to route the flow of exhaust gas 124 to the exhaust gas heatexchanger 112, open cycle absorption system 114 and the turbo-compressor128. The recycled plastic processing system 110 is operable to removeheat from the flow of exhaust gas 124 to melt solid recyclable plasticmaterial 308 to provide a flow of molten recyclable plastic material310. The molten recyclable plastic material 310 is operable to be cooledinto a solid recycled plastic products 312, such as recycled plasticbottles 312A, plastic bags, plastic furniture 312B, plastic pipes,plastic tee shirts or other plastic clothing 312C, plastic auto parts orany other like plastic products that can be formed from the moltenrecyclable plastic material 310.

The extruder 300 includes a hopper section 302, an auger mechanism 304and an extruder heat exchanger system 306. The hopper section 302 isoperable to receive the solid recyclable plastic material 308 therein.The solid recyclable plastic material 308 may be ground up plasticmaterial collected from industrial sources, residential sources, or thelike. The auger mechanism 304 is operable to receive the solidrecyclable plastic material 308 from the hopper section 302 and tocompress the solid recyclable plastic material 308 therein.

The extruder heat exchanger system 306 is operable to receive the flowof exhaust gas 124 from the turbo-expander 126 and to route the flow ofexhaust gas 124 to either of the exhaust gas heat exchanger 112, theopen cycle absorption system 114 and the turbo-compressor 128. Theextruder heat exchanger system 306 is operable to remove heat from theflow of exhaust gas 124 and to melt the solid recyclable plasticmaterial 308 in the auger mechanism 304 to provide the flow of moltenrecyclable plastic material 310 as the solid recyclable plastic material308 passes through the auger mechanism 304 and as the exhaust gas 124passes through the extruder heat exchanger system 306.

The extruder heat exchanger system 306 may be a single heat exchangerthat is operable to transfer heat directly from the exhaust gas 124 tothe solid recyclable plastic material 308 in the auger mechanism 304.Alternatively, the extruder heat exchanger 306 may include a pluralityof heat exchanger devices, that transfers the heat energy from theexhaust gas 124 in steps. For example, an exhaust gas to water heatexchanger may be used to transfer heat from the exhaust gas to a flow ofwater. Then a water to recyclable plastic heat exchanger may be used totransfer the heat energy from the flow of water to the solid recyclableplastic material 308 in the auger mechanism 304.

Though the exemplary embodiments illustrated in the FIGS. depicts theexhaust gas 124 being routed through a combined power system 100 priorto entering the recycled plastic processing system 110, it is within thescope of this disclosure that such a recycled plastic processing system110 may be used in other embodiments as well. For example, the exhaustgas 124 may be generated from a combustion process of a primary powersystem 102 and routed directly to the recycled plastic processing system110, without going through a bottoming cycle power system 104.Additionally, the combustion process may be generated from a sourceother than a primary power system 102, such as from a furnace system orfrom burning natural gas at an oil well site. Moreover, utilizing arecycled plastic processing system 110 to manufacture recycled plasticproducts from exhaust gas 124 generated by a combustion process of, forexample, a primary power system 102, may significantly reduce the costof manufacturing equivalent recycled plastic products from moreconventional sources of heat, such as electric heat, regardless ofwhether or not a bottoming cycle power system 104 is utilized.

Referring to FIG. 6 , an example is depicted of a flow diagram of amethod 400 of generating electrical power, in accordance with thepresent disclosure. The method may utilize one or more of the examplesof the power systems (e.g., combined power system 100, primary powersystem 102, bottoming cycle power system 104) describe herein. 0096. Themethod may also utilize any internal combustion engine (such as aturbine engine or a piston engine) that produces a combustion processand generates an exhaust gas. Further, the method may be utilized inassociation with any system that produces a combustion process andgenerates an exhaust gas, whether or not the system is deliveringelectrical power. For example the exhaust gas may be produced from afurnace system, or from burning natural gas at an oil well site or thelike.

The method 400 (FIG. 6 ), as well as the following method 450 (FIGS. 7Aand 7B), method 500 (FIG. 8 ) and method 550 (FIG. 9 ) depictnon-limiting examples of various steps of carrying out the methods.However, the order in which the steps of each method are executed maynot coincide with the order in which the steps are illustrated in eachof FIGS. 6, 7A, 7B, 8 and 9 . For example, the generating step 422 mayoccur prior to the transferring heat step 420 in FIG. 6 . Additionally,certain steps may be left out and certain other unillustrated steps maybe added to the illustrated methods. For example, the routing step 404,may be left out of the method 400 of FIG. 6 .

At 402, the method expands a flow of exhaust gas 124 from a combustionprocess as the exhaust gas 124 passes through and rotates aturbo-expander 126 disposed on a turbo-crankshaft 130. The combustionprocess and exhaust gas 124 may be associated with any system thatproduces a combustion process and generates an exhaust gas. By way ofexample, the flow of exhaust gas 124 may be generated from a primarypower system 102. The primary power system 102 may include an internalcombustion engine 116 having a rotatable crankshaft 118. The engine 116may be operable to use fuel in a combustion process to deliver power tothe engine crankshaft 118 and generate electricity and/or electricalpower 122 from a primary electric generator 120 disposed on the enginecrankshaft 118. The combustion process of the primary power system 102may produce the flow of exhaust gas 124 to the turbo-expander 126.

At 404, the flow of exhaust gas 124 from the turbo-expander 126 may berouted through a recycled plastic processing system 110 to producerecycled plastic products 312A, B and C. The recycled plastic processingsystem 110 additionally serves to cool the exhaust gas 124.Alternatively, the recycled plastic processing system 110 may be leftout of method 400. 0100. At 406, the flow of exhaust gas 124 from theturbo-expander 126 may be routed through a first flow path 136 of anexhaust gas heat exchanger 112. Alternatively, the exhaust gas heatexchanger 112 may be left out of method 400.

At 408, the flow of exhaust gas 124 from the turbo-expander 126 isrouted through an absorber section 150 of an open cycle absorptionchiller system 114.

At 410, water from the exhaust gas 124 is absorbed via a firstrefrigerant solution 158 disposed in the absorber section 150 as theexhaust gas 124 passes through the first refrigerant solution 158 andout of the absorber section 150. Wherein the absorbing of the waterreduces the concentration of water in the flow of exhaust gas 124 to nomore than 5.0 percent by weight, no more than 2.5 percent by weight orno more than 0.5 percent by weight before the flow of exhaust gas 124exits the absorber section 150. The first refrigerant solution 158 maybe a solution of water and a hygroscopic substance such as, for example,salt. The salt may be lithium bromide, lithium chloride or the like.

At 412, the flow of exhaust gas 124 from the absorber section 150 may becompressed as the exhaust gas 124 passes through a turbo-compressor 128disposed on the turbo-crankshaft 130.

At 414, the flow of exhaust gas 124 from the turbo-compressor 128 may berouted through a carbon dioxide capture system 106. Alternatively, thecarbon dioxide capture system may be left out of the method 400.

At 416, carbon dioxide 206 may be absorbed from the flow of exhaust gas124 as the exhaust gas 124 passes through the carbon dioxide capturesystem 106.

At 418, the flow of exhaust gas from the carbon dioxide capture systemmay be routed to a second flow path 138 of the exhaust gas heatexchanger 112. 0107. At 420, heat from the exhaust gas 124 in the firstflow path 136 may be transferred to the exhaust gas 124 in the secondflow path 138 as the flow of exhaust gas 124 passes through the firstand second flow paths of the exhaust gas heat exchanger 112. The exhaustgas heat exchanger 112 serves to cool the exhaust gas 124 in the firstflow path 136 prior to entering the turbo-compressor 128, thereforereducing the work required by the turbo-compressor 128 to compress theexhaust gas 124. Additionally, the exhaust gas heat exchanger 112 alsoserves to heat the exhaust gas 124 in the second flow path 136 prior toentering the stack 140, therefore enabling the exhaust gas 124 to morereadily flow up the stack 140.

At 422, electrical power 134 may be generated from a rotating bottomingcycle generator 132 disposed on the turbo-crankshaft 130. The electricalpower 134 may be used to supplement electrical power 122 from, forexample, a primary power system 102 that is generating the exhaust gas124.

Referring to FIG. 7A, an example is depicted of a flow diagram of amethod 450 of capturing carbon dioxide 206, in accordance with thepresent disclosure. Method 450 may be considered a subset of method 400,in that it is an expansion of the optional steps 414 and 416 of routingthe exhaust gas 124 through a carbon dioxide capture system 106 andabsorbing carbon dioxide from the exhaust gas 124. Alternatively, themethod 450 may not be a subset of method 400, but rather may be anindependent method for processing exhaust gas 124 in and of itself.

At 452, a flow of exhaust gas 124 is routed from a combustion processthrough an absorber section 150 of an open cycle absorption chillersystem 114. The flow of exhaust gas 124 may be from a turbo-compressor126 of a combined power system 100 as illustrated in FIG. 1 .Alternatively, the flow of exhaust gas 124 may be generated from anyinternal combustion engine (such as a turbine engine or a piston engine)that produces a combustion process and generates an exhaust gas.Further, the flow of exhaust gas 124 may be generated from any systemthat produces a combustion process and generates an exhaust gas, whetheror not the system includes an internal combustion engine. For example,the exhaust gas may be produced from a furnace system, or from burningnatural gas at an oil well site or the like. 0111. At 454, water fromthe exhaust gas 124 is absorbed via a first refrigerant solution 158disposed in the absorber section 150 as the exhaust gas 124 passesthrough the first refrigerant solution 158 and out of the absorbersection 150. Wherein the absorbing of the water reduces theconcentration of water in the flow of exhaust gas 124 to no more than5.0 percent by weight, no more than 2.5 percent by weight or no morethan 0.5 percent by weight before the flow of exhaust gas 124 exits theabsorber section 150.

At 456, the flow of exhaust gas 124 is routed into a first capture tank200 of a carbon dioxide capture system 106.

At 458, carbon dioxide 206 may be absorbed in the first capture tank 200from the exhaust gas 124 with first carbon dioxide absorbent material204 disposed in the first capture tank 200. The carbon dioxide absorbentmaterial 204 may be, for example, zeolite, metal organic frameworksmaterial, calcium hydroxide or the like.

At 460, the flow of exhaust gas 124 may be routed out of the firstcapture tank 200. By way of example, the flow of exhaust gas 124 may berouted out of the first capture tank 200 and to a stack 140 associatedwith the combustion process. Additionally, the flow of exhaust gas 124,may be routed to the second flow path 138 of an exhaust gas heatexchanger 112 as illustrated in FIG. 1 .

At 462, a compressor coolant loop 222 may be connected between a carbondioxide compressor 220 and a second capture tank 202 of the carbondioxide capture system 106. The second capture tank 202 may have asecond carbon dioxide absorbent material 204 disposed therein. Thecompressor coolant loop 222 may be, for example, connectable anddisconnectable between the carbon dioxide compressor 220 and the firstand/or second capture tanks 200, 202 via a plurality of compressorcoolant loop flow valve 236, 238, 240 and 242, as illustrated in FIG. 4.

At 464, a compressor coolant fluid 224 may be circulated through thecompressor coolant loop 222. The compressor coolant fluid 224 may be,for example, water, glycol or the like.

At 466, a heat of compression from the carbon dioxide compressor 220 istransferred to the second capture tank 202 via the compressor coolantfluid 224.

At 468, carbon dioxide 206 is regenerated from the second carbon dioxideabsorbent material 204 disposed in the second capture tank 202 with theheat of compression.

At 470, the regenerated carbon dioxide 206 from the second capture tank202 is compressed with the carbon dioxide compressor 220.

At 472, the regenerated carbon dioxide 206 from the second capture tank202 is pumped into a holding tank 232 via the carbon dioxide compressor220.

Referring to FIG. 7B, an example is depicted of a continuation of theflow diagram of the method 400 of capturing carbon dioxide, inaccordance with the present disclosure.

At 474, The compressor coolant loop 222 is switched such that it isdisconnected from the second capture tank 202 and reconnected betweenthe first capture tank 200 and the carbon dioxide compressor 220, whenthe first carbon dioxide absorbent material 204 in the first capturetank 200 has absorbed a predetermined amount of carbon dioxide 206.Essentially, when the carbon dioxide absorbent material 204 in the firstcapture tank 200 has reached a predetermined capacity limit, the flowvalves 236, 238, 240 and 242 are switched such that the compressorcoolant loop 222 now redirects the compressor coolant fluid 224 to flowbetween the carbon dioxide compressor 220 and the first capture tank200.

At 476, the flow of exhaust gas 124 is routed into the second capturetank 202. The flow of exhaust gas 124 may be coming from aturbo-compressor 124 as illustrated in FIG. 1 . 0124. At 478, the carbondioxide 206 is absorbed in the second capture tank 202 from the exhaustgas 124 with the second carbon dioxide absorbent material 204 disposedin the second capture tank 202.

At 480, the flow of exhaust gas 124 is routed out of the second capturetank 202. By way of example, the flow of exhaust gas 124 may be routedout of the second capture tank 202 and to a stack 140 associated withthe combustion process. Additionally, the flow of exhaust gas 124, maybe routed to the second flow path 138 of an exhaust gas heat exchanger112 as illustrated in FIG. 1 .

At 482, a heat of compression is transferred from the carbon dioxidecompressor 220 to the first capture tank 200 via the compressor coolantfluid 224 circulating in the compressor coolant loop 222.

At 484, carbon dioxide 206 is regenerated from the first carbon dioxideabsorbent material 204 with the heat of compression.

At 486, the regenerated carbon dioxide 206 from the first capture tank200 is compressed with the carbon dioxide compressor 220.

At 488, the regenerated carbon dioxide 206 is pumped from the firstcapture tank 200 into a holding tank 232 via the carbon dioxidecompressor 220.

Referring to FIG. 8 , an example is depicted of a flow diagram of amethod 500 of producing distilled water 176 and other distilled waterproducts such as DEF 183, in accordance with the present invention.Method 500 may be considered a subset of method 400, in that it is anexpansion of the step 410 of absorbing water from the exhaust gas 124.Alternatively, the method 500 may not be a subset of method 400, butrather may be an independent method for processing exhaust gas 124 andproducing distilled water products 176, 183 in and of itself 0131. At502, a flow of exhaust gas 124 from a combustion process is routedthrough a generator section heat exchanger 156 of a generator section152 of an open cycle absorption chiller system 114. The flow of exhaustgas 124 may be from a turbo-compressor 126 of a combined power system100 as illustrated in FIG. 1 . Alternatively, the flow of exhaust gas124 may be generated from any internal combustion engine (such as aturbine engine or a piston engine) that produces a combustion processand generates an exhaust gas. Further, the flow of exhaust gas 124 maybe generated from any system that produces a combustion process andgenerates an exhaust gas, whether or not the system includes an internalcombustion engine. For example, the exhaust gas may be produced from afurnace system, or from burning natural gas at an oil well site or thelike.

At 504, the flow of exhaust gas is routed from the generator sectionheat exchanger 156 through an absorber section 150 of the open cycleabsorption chiller system 114.

At 506, water from the exhaust gas 124 is absorbed via a firstrefrigerant solution 158 disposed in the absorber section 150 as theexhaust gas 124 passes through the first refrigerant solution 138 andout of the absorber section 150. Wherein the absorbing of the waterreduces the concentration of water in the flow of exhaust gas 124 to nomore than 5.0 percent by weight, no more than 2.5 percent by weight orno more than 0.5 percent by weight before the flow of exhaust gas 124exits the absorber section 150. The first refrigerant solution 158 maybe a solution of water and a hygroscopic substance such as, for example,salt. The salt may be lithium bromide, lithium chloride or the like.

At 508, heat from the exhaust gas 124 passing through the generatorsection heat exchanger 156 is absorbed into a second refrigerantsolution 160 disposed in the generator section 152. The secondrefrigerant solution 160 being in fluid communication with the firstrefrigerant solution 158.

At 509, because the first and second refrigerant solutions 158, 160 arein fluid communication with each other, a refrigerant solution pump 162may be used to pump the first refrigerant solution 158, including waterabsorbed from the exhaust gas 124 into the first refrigerant solution158, from the absorber section 150 to the generator section 160. Thefirst refrigerant solution 158, including the water absorbed from theexhaust gas 124, then mixes into the second refrigerant solution 160 inthe generator section 152.

At 510, water from the second refrigerant solution 160 is evaporatedwith the heat absorbed from the exhaust gas 124 to generate a flow ofsteam 168. The flow of steam 168 comprises a portion of the same waterabsorbed from the flow of exhaust gas 124 passing through the absorbersection 150. Moreover, the flow of steam 168 may comprise substantiallyall of the same water absorbed from the flow of exhaust gas 124 passingthrough the absorber section 150.

Uniquely, the heat absorbed from the exhaust gas 124 in the generatorsection 152 is used to evaporate out of the second refrigerant solution160 the water absorbed from the exhaust gas 124 into the firstrefrigerant solution 158 in the absorber section 150. Advantageouslywithin this open cycle absorption chiller system 114, most of the energyrequired to remove, evaporate and distill water from the exhaust gas 124is provided by the heat energy of the exhaust gas 124 itself. Also,advantageously within this system 114, a substantial amount ofevaporative cooling of the exhaust gas 124 is provided by the waterabsorbed from the exhaust gas 124 itself. Accordingly, the exhaust gas124 is both dried and cooled with very little energy consumed fromsources outside of the energy contained within the exhaust gas 124. As aresult, the exhaust gas 124, having been dried and cooled by theuniquely configured open cycle absorption chiller system 114, can moreeasily be compressed by turbo-compressor 128 and can more efficientlyhave its carbon dioxide removed by carbon dioxide capture system 106.

At 512, the flow of steam 168 is condensed in a condenser section 154 ofthe open cycle absorption chiller system 114 into a flow of liquiddistilled water 176 to produce distilled water products. The flow ofliquid distilled water 176 comprising a portion of the same waterabsorbed from the flow of exhaust gas 124 in the absorber section 150.Moreover, the flow of liquid distilled water 176 may comprisesubstantially all of the same water absorbed from the flow of exhaustgas 124 passing through the absorber section 150.

At 514, urea 181 is added to the liquid distilled water 176 to producediesel exhaust fluid 183.

Referring to FIG. 9 , an example is depicted of a flow diagram of amethod 550 of producing recycled plastic products 312A, 312B, 312C, inaccordance with the present disclosure. Method 550 may be considered asubset of method 400, in that it is an expansion of the step 404 ofrouting the flow of exhaust gas 124 from the turbo-expander 126 througha recycled plastic processing system 110. Alternatively, the method 550may not be a subset of method 400, but rather may be an independentmethod for processing exhaust gas 124 and producing recycled plasticproducts 312A, 312B, 312C in and of itself.

At 552, a flow of exhaust gas 124 from a combustion process is routedthrough an extruder heat exchanger system 306 of a plastic extruder 300of a recycled plastic processing system 110. The flow of exhaust gas 124may be expanded as the exhaust gas passes through and rotates aturbo-expander 126 disposed on a turbo-crankshaft 130, prior to passingthrough the extruder heat exchanger system 306. The flow of exhaust gas124 may be from a combined power system 100 as illustrated in FIG. 1 .Alternatively, the flow of exhaust gas 124 may be generated from anyinternal combustion engine (such as a turbine engine or a piston engine)that produces a combustion process and generates an exhaust gas.Further, the flow of exhaust gas 124 may be generated from any systemthat produces a combustion process and generates an exhaust gas, whetheror not the system includes an internal combustion engine. For example,the exhaust gas may be produced from a furnace system, or from burningnatural gas at an oil well site or the like.

At 554, heat from the exhaust gas 124 passing through the extruder heatexchanger system 306 is absorbed into solid recyclable plastic material308 disposed in an auger mechanism 304 of the plastic extruder 300. Theflow of exhaust gas 124 from the extruder heat exchanger system 306 maybe compressed as the exhaust gas 124 passes through a turbo-compressor128. Alternatively, the flow of exhaust gas 124 from the extruder heatexchanger system 306 may be routed directly to a stack 140. 0143. At556, the solid recyclable plastic material 308 is melted in the augermechanism 304 to provide a flow of molten recyclable plastic material310. In addition to providing heat from the exhaust gas 124, the augermechanism 304 may compress the solid recyclable plastic material 308 toenhance the melting process.

At 558, the molten recyclable plastic material 310 is cooled andprocessed into recycled plastic products 312, such as recycle plasticbottles 312A, recycled plastic furniture 312B and/or recycled plasticclothing 312B.

It should be appreciated that all combinations of the foregoing conceptsand additional concepts discussed in greater detail herein (providedsuch concepts are not mutually inconsistent) are contemplated as beingpart of the inventive subject matter disclosed herein. In particular,all combinations of claimed subject matter appearing at the end of thisdisclosure are contemplated as being part of the inventive subjectmatter disclosed herein.

Although the invention has been described by reference to specificexamples, it should be understood that numerous changes may be madewithin the spirit and scope of the inventive concepts described.Accordingly, it is intended that the disclosure not be limited to thedescribed examples, but that it have the full scope defined by thelanguage of the following claims.

What is claimed is:
 1. A bottoming cycle power system comprising: aturbo-expander operable to rotate a turbo-crankshaft as a flow ofexhaust gas from a combustion process passes through the turbo-expander,and a turbo-compressor operable to compress the flow of exhaust gasafter the exhaust gas passes through the turbo-expander; and an opencycle absorption chiller system comprising: an absorber section operableto receive the flow of exhaust gas from the turbo-expander and to mixthe flow of exhaust gas with a first refrigerant solution within theabsorber section, the first refrigerant solution operable to absorbwater from the exhaust gas as the exhaust gas passes through the firstrefrigerant solution, and the absorber section operable to route theflow of exhaust gas to the turbo-compressor after the flow of exhaustgas has passed through the first refrigerant solution.
 2. The bottomingcycle power system of claim 1, comprising a bottoming cycle generatordisposed on the turbo-crankshaft, the bottoming cycle generator operableto generate electrical power when the turbo-crankshaft is rotated by theturbo-expander.
 3. The bottoming cycle power system of claim 1,comprising the absorber section operable to reduce the concentration ofwater in the flow of exhaust gas to no more than 5.0 percent by weightbefore the flow of exhaust gas exits the absorber section.
 4. Thebottoming cycle power system of claim 1, wherein the open cycleabsorption chiller system comprises: a generator section operable tocontain a second refrigerant solution in fluid communication with thefirst refrigerant solution of the absorber section, the generatorsection comprising a generator section heat exchanger operable toreceive the flow of exhaust gas from the turbo-expander, the generatorsection heat exchanger operable to remove heat from the flow of exhaustgas to evaporate water from the second refrigerant solution and togenerate a flow of steam as the exhaust gas passes through the generatorsection heat exchanger, the flow of steam comprising a portion of thesame water absorbed from the flow of exhaust gas in the absorbersection.
 5. The bottoming cycle power system of claim 4, wherein theopen cycle absorption chiller system comprises: a condenser sectionoperable to be in fluid communication with the flow of steam from thegenerator section, the condenser section operable to remove heat fromthe flow of steam and to condense the flow of steam into a flow ofliquid water, the flow of liquid water comprising a portion of the samewater absorbed from the flow of exhaust gas in the absorber section. 6.The bottoming cycle power system of claim 5, wherein the open cycleabsorption chiller system comprises: a water pump in fluid communicationwith the condenser section, the water pump operable to pump the flow ofliquid water into a water tank.
 7. The bottoming cycle power system ofclaim 1, comprising: a recycled plastic processing system operable toreceive the flow of exhaust gas from the turbo-expander and to route theflow of exhaust gas to the open cycle absorption system, the recycledplastic processing system operable to remove heat from the flow ofexhaust gas to melt solid recyclable plastic material to provide a flowof molten recyclable plastic material, the molten recyclable plasticmaterial operable to be cooled into a solid recycled plastic product. 8.The bottoming cycle power system of claim 7, wherein the recycledplastic processing system comprises an extruder, the extrudercomprising: a hopper section operable to receive the solid recyclableplastic material therein; an auger mechanism operable to receive thesolid recyclable plastic material from the hopper section and tocompress the solid recyclable plastic material therein; and an extruderheat exchanger system operable to receive the flow of exhaust gas fromthe turbo-expander and to route the flow of exhaust gas to the opencycle absorption system, the extruder heat exchanger system operable toremove heat from the flow of exhaust gas and to melt the solidrecyclable plastic material in the auger mechanism to provide the flowof molten recyclable plastic material as the solid recyclable plasticmaterial passes through the auger mechanism and as the exhaust gaspasses through the extruder heat exchanger system.
 9. The bottomingcycle power system of claim 7, comprising a bottoming cycle generatordisposed on the turbo-crankshaft, the bottoming cycle generator operableto generate electrical power to operate the recycled plastic processingsystem when the turbo-crankshaft is rotated by the turbo-expander. 10.The bottoming cycle power system of claim 1, comprising: an exhaust gasheat exchanger comprising first and second flow paths operable toexchange heat therebetween, wherein: the first flow path is operable toreceive the flow of exhaust gas from the turbo-expander prior to theexhaust gas being compressed by the turbo-compressor, and the secondflow path is operable to receive the flow of exhaust gas from theturbo-compressor after the exhaust gas has been compressed by theturbo-compressor.
 11. The bottoming cycle power system of claim 10,wherein the first flow path of exhaust gas heat exchanger is operable toroute the flow of exhaust gas to the open cycle absorption system. 12.The bottoming cycle power system of claim 7, comprising: an exhaust gasheat exchanger comprising first and second flow paths operable toexchange heat therebetween, wherein: the first flow path is operable toreceive the flow of exhaust gas from the recycled plastic processingsystem prior to the exhaust gas being compressed by theturbo-compressor, and the second flow path is operable to receive theflow of exhaust gas from the turbo-compressor after the exhaust gas hasbeen compressed by the turbo-compressor.
 13. The bottoming cycle powersystem of claim 12, wherein the first flow path of exhaust gas heatexchanger is operable to route the flow of exhaust gas to the open cycleabsorption system.
 14. The bottoming cycle power system of claim 1,comprising a carbon dioxide capture system, the carbon dioxide capturesystem comprising: a first and a second capture tank, each capture tankcontaining carbon dioxide absorbent material operable to absorb carbondioxide from the exhaust gas, the first and second capture tanks eachcomprising: an exhaust gas inlet port selectively connectable to theflow of exhaust gas from the turbo-compressor, an exhaust gas outletport selectively connectable to the second flow path of the exhaust gasheat exchanger, and a carbon dioxide outlet port; a carbon dioxidecompressor selectively connectable to the carbon dioxide outlet port ofeither the first or second capture tank, the carbon dioxide compressoroperable to pump carbon dioxide out of the carbon dioxide outlet portthat the carbon dioxide compressor is connected to; and a compressorcoolant loop selectively connectable between the carbon dioxidecompressor and the first capture tank or between the carbon dioxidecompressor and the second capture tank, the compressor coolant loopoperable to flow a compressor coolant fluid to remove heat ofcompression from the compressor and to transfer the heat of compressionto the first or second capture tank, wherein the heat of compression isoperable to release a portion of the carbon dioxide absorbed by thecarbon dioxide absorbent material in the first or second capture tank.